Ready References
Overview of Motion Control
AAVSO Observing Programs
Signal Generators and Their Uses
Making Variable Star Observations
Choosing Binoculars for Astronomy
Hardware Hunting
The Severity of an Earthquake
Ready References 
Overview of Motion Control 
AAVSO Observing Programs Signal Generators and Their Uses Making Variable Star Observations Choosing Binoculars for Astronomy 
Hardware Hunting The Severity of an Earthquake